The relative pronounswho and whom both refer to people, and they commonly appear in relative clauses. Here's how to tell them apart.

Usage

Use who when a sentence requires a subject pronoun (equivalent to he or she).

In formal English, use whom when a sentence requires an object pronoun (equivalent to him or her).

See the usage notes below. Also see:

• Commonly Confused Words: I and Me
• Commonly Confused Words: Who, Which, and That

• Commonly Confused Words: Whoever and Whomever
• Hypercorrection
• Using the Different Forms of Pronouns
• Wh- Words

Examples

• "Dean Jackson, a tall, thin, quiet man, who was also a part-time Sunday school teacher, gave a scream like a falling tree, leaned back on thin air and punched Reverend Taylor on the arm."
  (Maya Angelou, I Know Why the Caged Bird Sings, 1970)
• "Mrs. Branthwaite inhabited the house on the corner. She was a known witch whom we often persecuted after dark by throwing gravel on her roof."
  (Clive James, Unreliable Memoirs, 1980)
• "A circus is like a mother in whom one can confide and who rewards and punishes."
  (Burt Lancaster)
• "How unbearable at times are people who are happy, people for whom everything works out."
  (Anton Chekhov)
• "We always love those who admire us, but we do not always love those whom we admire."
  (Francois de La Rochefoucauld)
• "Anger hurts the one who is possessed by it more than the one against whom it is directed."
  (Carl Sandburg)
• "Marriage is the alliance of two people, one of whom never remembers birthdays and the other who never forgets them."
  (Ogden Nash)

 

Corrections

• "English department: from page 3, July 19: 'The academic--whom authorities have long believed was connected to the group--was seized on Wednesday . . ..' That should be who, not whom."
  (Corrections and Clarifications, The Guardian, July 2, 2002)
• "'Oh, I'm not complaining,' said Chuffy, looking rather like Saint Sebastian on receipt of about the fifteenth arrow. 'You have a perfect right to love who you like . . .'
  
  "'Whom, old man,' I couldn't help saying. Jeeves has made me rather a purist in these matters."
  (P.G. Wodehouse, Thank You, Jeeves, 1934)
• "When Thomas Hardy wrote 'Who are you speaking of?' (Far from the Madding Crowd, p. 70), the OED called it 'a grammatical error,' and then changed its mind in 1923, when The Oxford Shorter Dictionary noted "Whom is no longer current in natural colloquial speech.'"
  (Jim Quinn, American Tongue and Cheek. Pantheon Books, 1980)

Usage Notes

• It is . . . not surprising that writers from Shakespeare onward should often have interchanged who and whom. And though the distinction shows no signs of disappearing in formal style, strict adherence to the rules in informal discourse might be taken as evidence that the speaker or writer is paying undue attention to the form of what is said, possibly at the expense of its substance. In speech and informal writing who tends to predominate over whom; a sentence such as Who did John say he was going to support? will be regarded as quite natural, if strictly incorrect. By contrast, the use of whom where who would be required, as in Whom shall I say is calling? may be thought to betray a certain linguistic insecurity. When the relative pronoun stands for the object of a preposition that ends a sentence, whom is technically the correct form: the strict grammarian will insist on Whom (not who) did you give it to? But grammarians since Noah Webster have argued that the excessive formality of whom in these cases is at odds with the relative informality associated with the practice of placing the preposition in final position and that the use of who in these cases should be regarded as entirely acceptable."
  ("who," The American Heritage Dictionary of the English Language, 3rd edition, 1992)
• "Strictly speaking, it is correct to use who as the subject of a verb and whom as the object, e.g. 'Who saw you?' but 'Whom did you see?' It is also strictly right to use whom after a preposition, as in 'To whom were you talking just now?' In practice, few people follow this rule; most use who all the time, and a sentence like 'To whom were you talking?' can sound too formal."
  ("Who or Whom?" AskOxford.com, 2008)
• "In spite of the outraged howls of traditionalists, the word whom is all but dead in English, even in formal written English."
  (R.L. Trask, Mind the Gaffe: The Penguin Guide to Common Errors in English. Penguin, 2002)
• If in Doubt . . .
  "Use of whom has all but disappeared from spoken English, and seems to be going the same way in most forms of written English too. If you are not sure, it is much better to use who when whom would traditionally have been required than to use whom incorrectly for who, which will make you look not just wrong but wrong and pompous."
  (David Marsh, Guardian Style. Guardian Books, 2007)
• New Rules
  "Whom, I am thrilled to tell you, is dying. But it's death, I am less thrilled to tell you, has been slow. According to Google’s expansive collection of digitized books, the word has been on a steady decline since 1826. The 400-million-word Corpus of Historical American English records a similar slump. Articles in Time magazine included 3,352 instances of whom in the 1930s, 1,492 in the 1990s, and 902 in the 2000s. And the lapse hasn’t been limited to literature or journalism. In 1984, after all, the Ghostbusters weren’t wondering, 'Whom you gonna call?' . . .
  
  "We break the old rules . . . because new rules are, effectively, replacing them. Few of us still use whom in speech, and we’ve adopted that practice in our writing, particularly in more-casual forms (e-mails, texts, IMs). What scholars refer to as 'secondary orality,' the tendency of written language to adopt the characteristics of speech, is for many of us the new linguistic reality."
  (Megan Garber, "For Whom the Bell Tolls." The Atlantic, April 2013)
• English Majors
  TK: Say, I've always been confused about when to use "who" and when to use "whom"--in a sentence, you know. Is there any rule about that or does everybody just do whatever they want?
  
  GK: Well, it depends on whether the pronoun is the subject or the object in the clause. You use "who" if it refers to the subject. For example, "the man who shot Liberty Valance," in which "who" refers to the man, "who" is the subject. And you use "whom" to refer to the object. For example, "the man whom we recommend"--"whom" stands for the man and he is the object of the verb "recommend." You understand?
  
  TK: I think so.
  (Tom Keith and Garrison Keillor, "English Majors." A Prairie Home Companion, March 23, 2002)

Practice

(a) W. C. Fields thought that any man ______ hates dogs and babies can't be all bad.

(b) It's human nature to want to protect the speech of people with ______ we agree.

 

Answers to Practice Exercises

Glossary of Usage: Index of Commonly Confused Words